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How to work with blocks in CAD

How to work with blocks in CAD

When drawing or designing with CAD, we usually have graphics that are repeatedly used such as windows in buildings, nut and bearing in mechanical devices. All those graphics can be defined as blocks and inserted into the current drawings and other drawings or even used to establish a graphics library. Using the block in CAD can greatly improve the drawing efficiency and quality of the drawing. In today’s post, we are going to talk about some basics about the block in CAD.

* What is a block

We can define some graphics that can be repeatedly used as a whole, it can be directly used by inserting it to drawing when needed, this “whole” is a block.

* How to define blocks

1.Have some graphics to be defined.

2. Select the button in the Block tab, as shown in the following picture,

or we can enter B, then press enter, the Block Definition dialog box would appear as shown in the following picture,

3. Enter the block name in the dialog box, the name is like the ID card for the block.

4. Specify the base point of block.

a. Click the “Pick Point” button in the dialog box, as shown in the following picture.

b. Specify the point and now you should have opened the snap mode in order to snap some points as pick point.

Please note that the base point is the insertion point. Beginners would use the original point as base point instead of specifying a base point. In fact, the base point doesn’t have to be on the blocks, it can be anywhere. We can complete defining blocks even if we don’t specify the base point, the software will automatically use the origin of coordinates as base point of blocks, but this would cause inconvenience. If the block graphics are far away from the origin, the block would be far from the cursor and sometimes you can’t see it. The base point is usually a point that is easy to position, such as the center of circle.

5. Select the objects. All selected objects will be part of the block.

a. Click the “Select Objects” button, as shown in the following picture,

b. Window select objects.

c. Press Enter key or Space key to complete selecting objects.

Like other commands, we could also execute B command after selecting objects.

6. Click “OK” to finish the Block Definition.

* How to insert blocks

1.Click the “Insert” in the Block tab, as shown in the following picture,

or enter I, then press Enter, and a Insert dialog box would pop up.

Once defined, blocked can be repeatedly inserted and Insert command is, therefore more frequently used than the Block Definition, that’s why the icon for Insert is bigger.

2. The drop-down menu of the name tab shows all the blocks available for the current drawing. Select a block and we can see the preview of the selected block through the upper right window.

3. Click “OK” after selecting the block.

4. Specify the insertion point, as shown in the following picture,

The block would move along with the cursor if no insertion point has been specified.

If we click the “Browse” button in the Insert dialog box, we can insert drawing files (*.dwg\*.dxf) as blocks to other drawings.

* How to write blocks

To insert the same block to different drawings, we can not only define blocks in the current drawing but also write blocks as separate drawing files, which is block file. The command is WBLOCK (WB), just like defining block, we also need to select objects, set base point, the only difference is that we will save it as a file, as shown in the following picture,

These are the very basics of block, we will talk more about block over time about block reference, dynamic block, etc.

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